Description US Installations
1
1
,
2
2
Canadian Installations
2
,
3
3
J Clearance to non-
mechanical air supply inlet
to building or the
combustion air inlet to any
other appliance
6 in (15 cm) for appliances
≤ 10,000 Btuh (3 kW), 12 in
(30 cm) for appliances >
10,000 Btuh (3 kW) and ≤
100,000 Btuh (30 kW), 36
in (91 cm) for appliances
>100,000 Btuh (30 kW)
6 in (15 cm) for appliances
≤ 10,000 Btuh (3 kW), 9 in
(23 cm) for appliances >
10,000 Btuh (3 kW) and ≤
50,000 Btuh (15 kW), 12 in
(30 cm) for appliances >
50,000 Btuh (15 kW)
K Clearance to mechanical
air supply inlet
6 ft (1.83 m) 3 ft (91 cm) above if within
10 ft (3 m) horizontally
L Do not terminate above
paved sidewalk or paved
driveway
7 ft (2.13 m)
4
Vents cannot be located
above public walkways or
other areas where
condensate or vapor can
cause a nuisance or
hazard*
M Clearance under veranda,
porch, deck or balcony
12 in (30 cm)
5
*
Table 5 Vent/air inlet termination clearances
Warning
Important!: Maintain at least the minimum separation of exhaust vent termination from
boiler intake air as illustrated in Figure 20 , Figure 21 , Figure 22 and Figure 23 . Failure
to do so can result in a dangerous situation where exhaust gasses are re-ingested with
combustion air. Damage to the boiler can result from a failure to maintain these
separations. Third party vent termination kits and concentric wall penetration kits that
do not maintain these minimum separations must not be used. Improper installation
will void the warranty. Do not use proprietary InnoFlue or PolyPro PPs terminals
without specific approval from IBC.
Sidewall direct vent with separate vent and air pipes must be terminated as follows:
Locate the intake air and exhaust vent terminations on the same plane (side) of the
building.
1
In accordance with the current CAN/CSA-B149 Installation Codes.
2
If locally adopted installation codes specify clearances different than those illustrated, then the most stringent shall apply.
3
In accordance with the current ANSI Z223.1 / NFPA 54 National Fuel Gas Code.
4
A vent shall not terminate directly above a sidewalk or paved driveway that is located between two single family dwellings and serves both
dwellings.
5
Permitted only if veranda, porch, deck, or balcony is fully open on a minimum of two sides beneath the floor.
3.7.6 Sidewall vent termination